Selective Internal Radiation Therapy (SIRT)

Selective Internal Radiation Therapy (SIRT) is a form of targeted brachytherapy (radiation therapy) that was developed for the treatment of advanced liver cancers. The targeted treatment involves having tiny radioactive beads delivered through the blood stream to the liver tumors, where they will emit a form of radiation energy to destroy cancer cells. 

Purpose of SIRT therapy

SIRT is a targeted internal radiation therapy and it offers superselective therapy of tumors while effectively sparing healthy tissues in the liver. Patients with liver tumors that cannot be removed by surgery, or are not responding to other therapies may be referred to undergo this therapy. The aim of SIRT is to inhibit tumor growth and shrink  liver metastases. Sufficient shrinkage of a liver tumor promises a higher chance of a liver tumor removal via surgery.

Preparing for the Procedure

• Before the treatment, you will need to undergo a CT and/or MRI liver scan to assess the tumor volume. Blood tests will also be conducted
• Your chemotherapy may be put on hold 2 weeks prior to the SIRT procedure. Consult your medical oncologist for further advice
• You will be required to fast for 6 hours prior to the procedure. Water is permissible
• If you are a diabetic on Metformin, you will be required to stop your medication for 2 days prior to the procedure
• You will not be able to receive the SIRT treatment if you are pregnant
• Language interpretation services are available if required
   

You will be required to sign a consent form before undergoing SIRT.

Procedure

• You will be admitted into a ward on the day of the SIRT procedure. 
• Blood transfusions may be arranged if  needed and you will be given an antibiotic
• The treatment will be carried out via an Interventional Radiological Procedure (IRP)
  A catheter will be inserted into your hepatic artery where the radionuclide will be injected
• The treatment will be performed in an interventional suite where you will be awake throughout the procedure. You may request to be sedated
• The duration of the procedure can range from 1 to 3 hours, depending on complexity of the case
• Following IRP, you will be required to undergo an imaging test in the Nuclear Medicine Suite 
• Administration of SIRT may cause immediate short-term abdominal pain but it is typically self-limiting. You may be given an anesthesia for the pain
• After SIRT administration, your condition will be monitored for a few hours in the Nuclear Medicine Suite
• If there are no complications, you may be discharged once treatment is complete

Post Procedure

• A follow-up appointment will be arranged before you are discharged
• Your chemotherapy may be on hold for 2 weeks following SIRT administration. Consult your medical oncologist for further advice
• If you are a diabetic on Metformin, you may resume your medication 2 days after completion of procedure
• After the procedure, you may experience lethargy and nausea for up to two weeks
• You may also develop mild to moderate fever for several days. If symptoms persist beyond, please consult your doctor
• You must not get pregnant for at least 2 months after SIRT. In addition, you should not breastfeed in the two weeks after the procedure. Milk expressed during this period must not be given to your child
• Avoid close contact with infants or pregnant women
• You are encouraged to be on oral hydration for at least 2 days after the procedure
• After the procedure, the radiotracer will quickly decay and will be excreted through your urine
• Flush the toilet twice after each use. Avoid splashing while urinating to  prevent contamination
• Normal activities can be resumed after the procedure

For more enquiries or to make an appointment, call  (65) 6705 2777. 

Reference: 
1. https://theranostics.sg/yttrium-90-selective-internal-radiation-therapy/